This invention relates generally to mobile radios, and more particularly, to dual band full duplex mobile radios.
Land mobile radios may be used to provide communication between different mobile units. Land mobile radio band communication, and in particular, public safety radio communication (e.g., police, fire department, etc.), is available within the 800 MHz frequency band. Part of this frequency band is allocated by the Federal Communications Commission (FCC) for public safety communication services and is also referred to as the Public Safety Frequency Band. Communication with these land mobile radios for public safety communication services has been extended by the FCC and is now available on part of the 700 MHz frequency band.
Known land mobile radio units do not provide combined dual band operation with full duplex transmissions. In order to provide full duplex transmission operation, these land mobile radios use bandpass filters external to the radio (e.g., a separate unit connected to the radio). For example, known land mobile radios provide single band operation that uses an external duplexer filter assembly connected to the radio to provide full duplex transmissions. The duplexer isolates the receiver from the transmitter in the radio, allowing simultaneous transmission and reception by the radio using the same antenna. Thus, separate units or chassis are used to provide simplex, half duplex and full duplex modes of operation. However, although different modes of operation, including full duplex transmissions may be provided by these known land mobile radios using an external duplexer, these radios are only capable of operating in the in a single frequency band, and in particular, the 800 MHz trunked radio frequency band.
Thus, these known land mobile radios are not only limited in their operating frequency range, but require external components, such as a duplexer, in order to provide full duplex communication. This results in a more costly and complex radio. Further, these radios do not provide operation in the different Public Safety Frequency Bands, and in particular, the 700 MHz Public Safety Frequency Band.